Food is one of our basic requirements for life. It takes centre stage in family rituals and celebrations and is the star of many of the world’s most popular Instagram feeds. Yet every year one-third of the total amount the world produces – around 1.3 billion tonnes – is wasted.

According to Project Drawdown, which champions the 100 most impactful solutions to reduce global warming, reducing food waste is No.3 on the hit list. “If 50% of food waste is reduced by 2050, avoided emissions could be equal to 26.2 gigatons of carbon dioxide,” the Project says.

And that’s just for starters. “Reducing waste also avoids the deforestation for additional farmland, preventing 44.4 gigatons of additional emissions.”

Achieving the ambition of cutting food waste depends on action across all parts of the food supply chain: reducing emissions from agriculture, revisiting purchase patterns and redistributing food before it is wasted.

It’s an issue that Unilever’s Foods and Refreshment team are putting front and centre, covering product development, Unilever Food Solutions’ work with the restaurants around the world and the way consumers can rely on some of our most popular brands, such as Hellmann’s, for help in using leftovers and unloved ingredients in imaginative and tasty ways.

Here are just eight of the ways we’re rethinking food waste from product to plate:

Once, the leftover liquid from an open can of chickpeas was simply wasted. Not any more. The gloopy liquid called ‘aquafaba’ is the ‘secret sauce’ in New York-based condiment firm, Sir Kensington’s, vegan mayonnaise. The liquid can be whipped into white peaks in the same way as egg whites.

This has made it a hit with the vegan community as an egg substitute and has also seen it put to use to provide the great texture of Sir Kensington’s vegan alternative to mayonnaise, Fabanaise. Thanks to the company’s initial partnership with food firm Ithaca Hummus, tens of thousands of pounds of aquafaba has been saved from the drain and it is now a key ingredient in this loved product.

The brewing by-product that’s a toast topper the world over

Marmite is a brown pungent yeast spread that is loved and hated by consumers in equal measure. Produced in the brewing town of Burton upon Trent in the UK, its recipe has remained unchanged for more than 100 years.

Alongside the salt, vegetable juice concentrates, vitamins and natural celery flavouring, 90% of a local brewing company’s waste yeast is used as an ingredient in the spread. And it doesn’t end there. By-products from Marmite’s own production are put to good use too. Part of the yeast by-product is used for animal feed; other waste is sent for anaerobic digestion which generates biogas, used to power the factory.

The green tomatoes that created a fresh new ketchup taste

The main ingredient in ketchup is red, not green tomatoes. Come harvest, only red tomatoes are processed, while more than 10% of the global tomato crop is wasted simply because it’s not red enough. “No one likes to see perfectly good food go to waste,” says Hellmann’s Brand Manager, Rhiannon Lines. After discussion with its Spanish tomato supplier, Agraz, Hellmann’s decided to see what would happen if every tomato was processed.

The result is Hellmann’s Ketchup Made with Red and Green Tomatoes, blended with herbs and spices to create a fresh new taste. It’s saved up to 2.5 million tomatoes a year. “With every squeeze, consumers are doing their bit to keep perfectly good tomatoes from going uneaten,” Rhiannon says.

The app offering meal plan ideas to reduce restaurant waste

Each time a guest eats at a restaurant, they create 0.5 kilos of waste – 30% comes from what’s left on their plate and 70% is produced in the kitchen. As well as the economic cost, every tonne of food wasted costs a business £1,800 (€1,950) and there’s a significant social and environmental impact.

The Waste and Reduction Action Programme (WRAP) estimates that one in every six out of home meals is thrown away. In a bid to rescue food within the Australian and New Zealand hospitality industry, Unilever Food Solutions (UFS) has teamed up with three charities, OzHarvest, KiwiHarvest and Kaibosh, to create The Food Collective, which rescues unwanted restaurant food and ingredients and distributes them to people in need.

To date, 110,000 meals have been redirected by these charities, saving people from going hungry and ensuring food goes to nourish people rather than heading to landfill. What’s more, for every case of UFS products purchased, 0.5 cent is donated to the charities, 0.5 cent equating to one meal for people in need.

The Greek hotels engaging staff and guests to cut waste

Piled high plates of fruit, cheeses, meats and breads all add to the luxury of a hotel buffet. Yet research reveals just over 50% is consumed. It’s this wastage that Unilever Food Solutions/WWF and three Greek hotels are working to change. The Grecotel Cape Sounio, Aquila Rithymna Beach, and Athens Marriott Hotel are currently taking part in a three-month pilot programme called WWF Hotel Kitchen: Here we value food.

It includes the implementation of food waste measures in the kitchen as well as informing staff and guests about their role in the responsible consumption of food. When the programme was first implemented in the US, food waste was reduced by 17%. The three Greek hotels hope for similar results.

The restaurants that turned leftover ingredients into five-star dishes

We can all relate to that moment when you look in the fridge and think there is nothing to eat. It’s called ‘fridge blindness’ and contributes to the 40% of food waste that happens at the household level. To tackle this issue, Hellmann’s launched the Bring Your Own Food restaurant in São Paulo and Prague to inspire people to turn leftover ingredients into delicious meals. Celebrity chefs turned these ingredients into five-star meals using Hellmann’s.

Instead of a bill, diners received a recipe of the ingredients used. Every dish became a recipe video and proved that Hellmann’s can make a delicious meal out of seemingly uninspiring ingredients and that food is too good to be wasted.

The brand that fed a stadium with rescued food

Every minute, enough food is wasted in Canada to feed a stadium. So Hellmann’s rescued food from local suppliers and turned it into delicious meals that were fed to an entire stadium free of charge. In a big screen reveal, the audience was made aware that the food they enjoyed was rescued.

They then learnt that Hellmann’s is partnering with MLSE (Maple Leaf Sports & Entertainment) and will collect the leftover food from stadium events and redistribute it to those in need, pledging to donate 50,000 meals. The video highlights the huge problem and provides a call to action to visit the brand’s site where consumers can get more information and ideas on how to reduce their own waste.